Python 判断字典键、值对是否满足用户定义的搜索条件

为此构建一个解析器并不困难.您可以使用operator包来处理条件，除此之外，它只是一堆格式化和循环数据.

import operator, re

# dictionary of operators
operators = {'<' :operator.lt,
             '<=':operator.le,
             '==':operator.eq,
             '>=':operator.ge,
             '>' :operator.gt,
             '!=':operator.ne
             }
        
# format operators keys for regex group
_oper = '|'.join(operators.keys())
        
# regex
oper   = re.compile(fr'\s*({_oper})\s*').split
number = re.compile(r'-?\d*(\.\d+)?').fullmatch
string = re.compile(r'("|\')(?P<str>.*)\1').fullmatch

def cast(value:str) -> float|int|bool|str|None:
    out = None
    
    if (v := value.lower()) in ('true', 'false'):
        out = v == "true"
    elif m := string(value):
        out = m.group('str')
    elif m := number(value):
        out = (int,float)['.' in v](v)
        
    return out

def check_conditions(data:dict, conditions:str) -> bool:
    # stores condition results
    facts = []

    for cond in conditions.split(','):
        # stores values and operators
        v, o = [], []
        
        # parse values and operators
        for c in oper(cond):
            if (c := c.strip()) in operators:
                # store operator function
                o.append(operators.get(c))
            else:
                # try data[c] else cast c
                v.append(data.get(c, cast(c)))
              
        # make sure values length is one more than operators              
        if (len(v) - len(o)) != 1:
            raise ValueError
            
        # call all operator functions on values and store results
        facts += [o[i](*v[i:i+2]) for i in range(len(o))]
    
    return all(facts)

usage

data  = {'a':25, 'ab':3.3, '(cd)': 4, 'ef':35, 'gh':.2, 'ij':"hello", 'kl':False, "mn":None}

conds = 'mn==None, a>5, 0<(cd)<5, 35==ef!=34>12<20, ij==\'hello\''  
print(check_conditions(data, conds)) #True